up 8 lbs?!

Can someone explain this? I have been working out diligently for 2 months, 6-7 days a week. I have gained 8 lbs since I started. Yes, I have been on 2 vacations and slipped a bit in my eating habits but other than that I have been eating 1200-1400 calories a day. I am even to the point of buying up a size in pants! Even my former trainer was a little stunned. I have lost an inch in the waist and hips and gained an inch in my arms, calves and thighs (I could do without the extra inch there.) Anyone know why this would happen? BTW, being pregnant is not a possibilty. Help!